• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 1997.04a
• /
• pp.362-369
• /
• 1997

In the case of a precision equipment, it requires a vibration free environment to provide its proper function. Especially, lithography and inspection devices, which have sub-nanometer class high accuracy and resolution, have come to necessity for producing more improved giga class semiconductor wafers. This high technology equipments require very strict environmental vibration standard in proportion to the accuracy of the manufacturing, inspecting devices. The vibration criteria of high sensitive equipment should be expressed in the form of 'exactness' and 'accuracy', because this is made basic data in the use of building structure design. This paper made a study on the specification of high sensitive equipment and proposed a contents of the specification.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2012.02a
• /
• pp.559-559
• /
• 2012

We developed a new scheme for the highly sensitive near-field scanning optical microscope (NSOM) by using a dithering sample stage rather than a dithering probe. In the proposed scheme, the sample is directly loaded on one prong surface of a dithering bare tuning fork. Gap control between probe and sample is performed by detecting the shear force between an immobile fiber probe and the dithering sample. In a conventional NSOM, the Q factor drastically decreases from 7783 to 1000 or even to 100 by attaching a probe to the tuning fork. In our proposed NSOM, on the contrary, the Q factor does not change significantly, 7783 to 7480, when the sample is loaded directly to the tuning fork instead of attaching a probe. Consequently, the graphene sheets that cannot be observed by a conventional NSOM were clearly observed by the proposed method with sub-nanometer vertical resolution due to the extremely high Q factor.

• Ceramist
• /
• v.22 no.4
• /
• pp.417-428
• /
• 2019

Even though, nanoscale materials of various shapes and compositions have been synthesized in the liquid, their underlying growth and transformation mechanisms are not well understood due to a lack of analytical methods. The advent of liquid cell for transmission electron microscope (TEM) enables the direct imaging of chemical reactions that occur in liquids with nanometer resolution of the electron microscope (EM). Here, the technical development of liquid cell TEM equipment and their applications to the study of nanomaterials analysis in liquid are discussed. Also new findings discovered through liquid cell TEM studies such as nucleation & growth, coalescence process and transformation are discussed.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2012.05a
• /
• pp.55.1-55.1
• /
• 2012

In the first part of this talk, I will introduce an effort to use gold nanoparticles and UO22+ (uranyl) specific DNAzyme for development of highly sensitive and selective colorimetric uranyl sensors. In addition, I will discuss how DNA aptamers can be delivered by nanoparticles to cancer cell nucleus and released by ultrafast femtosecond pulsed laser for targeted cancer therapy. Finally, I will show how proteins such as streptavidin and myoglobin, or nanoparticles can be precisely aligned on DNA with nanometer resolution via backbone-modified phosphorothioate DNA and bifunctional linkers. These interesting functional and structural properties of DNA can provide new opportunities to develop dynamic DNA structures for potential use as intracellular sensors and drug delivery agents.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.7 no.1
• /
• pp.32-37
• /
• 2008

This paper presents a new precision stage by using the PZT actuator and stepping motor. The stage have the precision positioning mechanism that has been developed for generation displacements with nanometer accuracy and a millimeter dynamic range simulatneously. The stage is composed not of the mechanical elastic hinge but of the clamp, and only one PZT actuator. The displacement of stage is acquired by the control of the two clamp between the PZT actuator. The results of the FEM analysis in the contact part of the clamp and basic properties of the positioning system are also presented. Using the new stage proposed in this paper.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.16 no.8
• /
• pp.1530-1535
• /
• 1992

An optical method of phase shifting interferometry is presented for the 3-dimensional profile measurement of mirror surfaces with nanometer resolution. A series of optical interferometric fringes are generated by comparing the surface to be measured with a reference flat. The fringes are captured by a CCD camera and then analyzed to obtain actual surface profile. Detailed principles are described along with necessary image processing algorithms. finally, several measurement examples are discussed which were performed on lapped surfaces, hard discs, and semiconductor wafers.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.10a
• /
• pp.149-153
• /
• 2005

The electron beam machining provides very high resolution up to nanometer scale, hence the E-beam writing technology is rapidly growing in MEMS and nano-engineering areas. In the optical column of the e-beam writer, there are several lenses condensing and focusing electron beams from electron gun with fringing magnetic fields. The polepieces of these lenses are usually made with high purity iron which is hard to fabricate and very expensive. In this paper, the possibility of using polepiece of object lens composed with pure iron and low carbon steel was examined to reduce cost. The magnetic field at object lens was calculated with finite element method, and practical focusing qualities of SEM pictures were observed comparing for the object lens polepieces with pure iron and two type of composed with low carbon steel.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2001.11b
• /
• pp.1376-1383
• /
• 2001

Modem technology depends on the reliability of extremely high technology equipments. In the production of semiconductor wafer, optical and electron microscopes, ion-beam, laser device must maintain their alignments within a sub-micrometer. This equipment requires a vibration free environment to provide its proper function. Especially, lithography and inspection devices, which have sub-nanometer class high accuracy and resolution, have come to necessity for producing more improved giga and tera class semiconductor wafers. This high technology equipments require very strict environmental vibration standard, vibration criteria, in proportion to the accuracy of the manufacturing, inspecting devices. The vibration criteria of high sensitive equipment should be represented in the form of 'exactness' and 'accuracy', because this is used as basic data for the design of building structure and structural dynamics of equipment. This paper deals with the properties of time and frequency domain in order to obtain more improved vibration criteria for high sensitive equipment.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 1996.10a
• /
• pp.377-385
• /
• 1996

In the case of a precision equipment, it requires a vibration free environment to provide its proper function. Especially, lithography and inspection devices, which have sub-nanometer class high accuracy and resolution, have come to necessity for producing more improved giga class semiconductor wafers. This high technology equipments require very strict environmental vibration standard in proportion to the accuracy of the manufacturing, inspecting devices. The vibration criteria are usually obtained either by the real vibration exciting test on the equipment or by the analytical calculation. the former is accurate but requires a great deal of time and efforts while the latter lacks reliability. this paper proposes a new method to solve this problem at a time. the permissible vibration level to a precision equipment can be easily obtained by analyzing a process of Frequency Response Function. This paper also demonstrates its effectiveness by applying the proposed method to finding the vibration criteria of a Computer Hard Disk Drive by impact Test.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
• /
• 2005.09a
• /
• pp.49-54
• /
• 2005

In the case of a sensitive equipment, it require a vibration free environment to provide its proper function. Especially, lithography and inspection device, which have sub-nanometer class high accuracy and resolution, have come to necessity for producing more improved Giga Class semi conductor wafers. The aim of this study is to evaluate the allowable vibration response of a precision inspect ion equipment, which has some trouble in field, by using experimental measurement data and to proposal a proper ant i-vibration method.